$OpenBSD: patch-Makefile_in,v 1.2 2014/02/06 17:32:27 edd Exp $

Fix grep syntax.

--- Makefile.in.orig2	Sun Feb  2 17:33:01 2014
+++ Makefile.in	Sun Feb  2 17:33:08 2014
@@ -1246,7 +1246,7 @@ dist-hook:
 	find $(distdir) -name CVS -type d -prune -exec rm -rf {} \;
 
 $(top_builddir)/graphviz_version.h: config.h
-	$(GREP) 'PACKAGE\|VERSION\|GVPLUGIN' config.h > $(top_builddir)/graphviz_version.h
+	$(GREP) -E '(PACKAGE|VERSION|GVPLUGIN)' config.h > graphviz_version.h
 
 .PHONY: rpm
 rpm: dist
